As for the first points, yes, that may happen, but is it a problem for users who already are part of a ‘better’ experience here than on the for-profit platforms?
I, for one, find much better discourse here than anywhere on reddit, let alone Meta or Twitter.
Also exemplified by me engaging much more here than ever on the others. I do prefer quality over quantity - everyone is invited to join the table, but I don’t see much benefit in luring people there who would ultimately only dilute or be disruptive - ie, not really into the thing that’s happening here.
For the last point, well, legislators can certainly try. While telling people it’s all for their benefit and upholding freedom and democracy and equal opportunity and whatnot. And even keep a straight face.